Various applications exist for the separation of gaseous mixtures. For example, the separation of nitrogen from atmospheric air can provide a highly concentrated source of oxygen. These various applications include the provision of elevated concentrations of oxygen for medical patients and flight personnel. Hence, it is desirable to provide systems that separate gaseous mixtures to provide a concentrated product gas, such as a breathing gas with a concentration of oxygen.
Several existing product gas or oxygen concentrators, for example, are disclosed in U.S. Pat. Nos. 4,449,990, 5,906,672, 5,917,135, 5,988,165, 7,455,717, 7,722,700, 7,875,105, 8,070,853, and 8,282,717, and U.S. Pat. Appl. Ser. Nos. 61/608,874, 61/661,260, and Ser. No. 13/790,312 which are commonly assigned to Invacare Corporation of Elyria, Ohio, and fully incorporated herein by reference.